A Body power brake booster firewall mount

I have installed a 440 with fender exit headers I am looking to raise my master cylinder up out of the heat pit. I was looking for a cantilever mount to do this mod. I can modify or build a custom if I need to. I would like the correct mount for my year car, if the 73 and later is different I'll be needed this later year then. If anyone can help me out I will appreciate your assistance.

Thank you, Eric..